The present invention relates to a fluorescent tube display useful with electronic calculators.
According to a conventional manner, as is seen from FIG. 1, an electronic calculator comprises a printed circuit flexible film 1, a multi-digit fluorescent tube display 2, a single chip LSI semiconductor 3 and stationary key contacts 4. With respect to the fluorescent tube display 2, see for example U.S. Pat. No. 3,571,655 issued to Akira Tanimoto and entitled ELECTRONIC INDICIA DISPLAY SYSTEM. The respective components have their lead wires which are connected to conductor leaves on the printed circuit flexible film 1 by solder welding. Terminals identified as 6 are to be connected a power source 7. The flexible film 1 further comprises through-hole connections 8 and rear connections 9. With such an arrangement, in case the fluorescent tube display is of the six-digit, eight segment type for example, the fluorescent tube display will be required to have 16 terminals as follows. These terminals should be bonded to the printed circuit flexible film 1 by solder welding.
______________________________________ Terminals for digit (or grid) selection 6 Terminals for segment selection 8 Terminals for filaments 2 ______________________________________
For the LSI semiconductor chip containing a data processor unit, there are 18 terminals to be bonded to the printed circuit flexible film 1 by solder welding.
______________________________________ Terminals for timing signals to be supplied to grids and key contacts 6 Terminals for segment signals 8 Terminals for key outputs 2 Terminals for power supply 2 ______________________________________
In this way, since the fluorescent tube display 2 and the LSI chip 3 are discrete components, many disadvantages arise, namely: an increased number of components; an increased number of solder weldings; and an increase in manufacturing costs and generation of condemned goods.
Accordingly, it is an object of the present invention to provide an improved fluorescent tube type display useful with electronic calculators or the like which avoids the above discussed disadvantages.
It is another object of the present invention to provide a new construction of combined fluorescent tube type displays and semiconductor chips to thereby assure simplicity in the manufacture thereof.
It is still another object of the present invention to provide an improved fluorescent tube type display wherein connections with the semiconductor chip are accomplished without passing through its external terminals.
It is another object of the present invention to provide an improved fluorescent tube type display in combination with an electronic calculator having a keyboard of the key strobing wherein the respective key switches in the keyboard are connected with the external terminals of the fluorescent tube display.